Union ALL with different number of columns

I have an Employee table with these columns :

• EmployeeId
• Fullname
• Phone
• Department
• Team
• Function
• Manager

and EmployeeHistory containing the history with different columns, but there are some in common :

• EmployeeId
• Fullname
• Email
• Geolocation
• Department
• Team
• Function
• Manager

How can I union them?

Answer

Replace uncommon columns by dummy values.

SELECT 
EmployeeId ,
Fullname   ,
'Undefined' AS Email,
Phone      ,
'Undefined' AS Geolocation
Department ,
Team       ,
[Function]   ,
Manager    
FROM Employee

UNION ALL

EmployeeId ,
Fullname   ,
Email      ,
'0000000000' AS Phone,
Geolocation,
Department ,
Team       ,
[Function]   ,
Manager    
FROM EmployeeHistory